Process for uniting metals



Patented Apr. 27, 1926.

UNITED STATES 1,582,024 PATENT. OFFICE.

GLEN D. BAGLEY, OF GREAT NECK, NEW YORK, ASSIGNOR TO ELECTED METALLUR- GICAL COMPANY, A CORPORATION OF \VEST VIRGINIA.

PROCESS FOR UNITING METALS.

No Drawing.

1 '0 all 'uizom it may concern:

Be it known that I, GLEN D. BAGLEY, a citizen of the United States, residing at (ircat Neck, Long Island, in the county of n Nassau and State of'New York, have invented certain new and useful Improvements in Processes for Uniting Metals, of which the following is a specification.

The invention is a process for uniting in metals of the chromium group, particularly tungsten, molybdenum and chromium, to copper and copper alloys.

In many cases, particularly in the construction of electrical apparatus, it is desirable to produce a strong sound union between metals such as the above. The metals of the chromium roup have very high melting points, and for this reason they are adapted for use as spark gap electrodes for high-frequency induction furnaces, as targets in X-ray tubes, and for other purposes. Tungsten is of course an excellent material -for incandescent lamp filaments. (topper and the copper alloys in general melt quite easily, but in contrast to metals of the chromium group they have very high electrical and heat conductivity; they are easily worked and machined; and they are readily joined to the common metals by brazing, welding or soldering. The desirability of combining all the above qualities in a single structural member is apparent, and it can be done with a composite member built up by joining a part consisting of copper or copper alloy to another part consisting of a metal of the chromium group.

It is, however, very difiicult to join the metals in question. The chromium group metals do not dissolve in copper nor alloy with it in the manner required in brazing.

Where a union is made by electroplating a chromium group metal and then attaching a member of copper or copper alloy to the plate, the union often fails when subjected to high temperatures and other drastic treatment.

In accordance with my invention, advantage is taken of the fact that nickle alloys withcopper and also with the chromium group metals. I therefore use nickel or its equivalent as the bonding agent.

The invention may be carried out in a variety of ways. The following specific examples are illustrative.

Application filed m 29,

A spark gap electrode was made by the following method: A layer of nickel was melted on the bottom of a graphite crucible. The nickel was highly superheated, and tungsten powder was dissolved in it until a layer of nickel-tungsten alloy containing tungsten was obtained. Copper was then melted on top of this alloy. Because of the high density of tungsten and the fact that it does not alloy with copper, the nickel-tungsten alloy remained under the copper, but where the two materials were in contact a nickel-copper alloy formed. ()n cooling the crucible, the two parts of the solidified ingot were found to be firmly united. The tungsten-nickel end was finished by grinding, and the copper end was machined, drilled, and tapped. There was no tendency for the metals to separate after several months use as a spark gap electrode.

A section of rolled sheet molybdenum was heated, and nickel was flowed over its upper surface. The metals united so firmly due to the formation of an alloy at the contacting surfaces that there was no tendency to separate after cooling even when the sheet was broken. A copper member was then firmly attached to the nickeled side of the sheet by brazing.

Having now described my invention, I claim:

1. Process of uniting a metal of the chromium group with copper or a copper alloy which comprises causing nickel to alloy with the first metal, at least at its surface, and then causing the cupriferous metal to alloy with the material so formed.

2. Process of uniting tungsten with copper or a copper alloy which comprises preparing a nickel-tungsten alloy and melting the cupriferous metal thereon until union is effected.

3. A composite member having one portion consisting principally of an element of the chromium group bonded with nickel to a1 1portion consisting of copper or a copper a 0y.

4. A composite member having a portion consisting of a nickel-tungsten alloy bonded to a portion consisting of copper.

5. A composite member having one por tion consisting of a nickel-tungsten alloy and another portion consisting of copper, and a bond therebetween comprising a coppernickel alloy.

6'. A composite member having one porof the chromium group, another portion tion consisting principally of an element of consisting of copper or a. copper alloy, and the chromium group, another portion coma bond comprising nickel alloyed to and 10 prising copper, and a metal alloyed to and uniting said portions.

5 uniting said portions. In testimony whereof, I aflix my signature.

A composite member having one portion consistmg principally of an element GLEN D. BAGLEY. 

